TALLAHASSEE, Fla., Sept. 2 (UPI) -- It's been theorized that dramatic changes in environment can precipitate rapid evolution and speciation.
A rapid rise in oxygen has been credited with spurring the Cambrian explosion, for example, while mammal biodiversity is thought have blossomed in the wake of the dinosaur's extinction.
Now, new research lends credence to the idea that rapid evolution often follows shifting environmental factors -- but with a twist. Study authors say their findings may have implications for a diverse array of research fields, from climate science to medicine.
Scientists at Florida State University highlighted the cause and effect by supplanting a population of guppies from their natural habitat, complete with predators, to two predator-free streams. Because guppies reproduce multiple times a year, they offer scientists a chance to track genetic changes over several generations in a relatively short amount of time.
In doing so, researchers happened upon an unexpected phenomenon.
Not only did the fish exhibit generational genetic adaptations, but also immediate changes in gene expression. What's more, these changes were often at odds with each other.
The immediate changes, genetic plasticity, were often reversed as the guppies' genetic code evolved from generation to generation.
"Some evolutionary theory suggests that plastic and evolutionary changes should be in the same direction," Kimberly Hughes, a professor of biological sciences at Florida State, explained in a press release. "But our results indicate that at least in the very early stages of evolution, genes that respond in the 'wrong' way to an environmental shift are those that will evolve most quickly."
Hugh and her colleagues -- whose work was detailed in the journal Nature -- likened the rapid environmental changes faced by the study's guppies to plants faced with rising global temperatures, or tumors faced with on onslaught of targeted radiation.
Hughes says the genetic plasticity of evolving tumors could be measured, just as it was in the guppies experiment.
"And then we might be able to predict how the pathogen or tumor will respond to treatment over longer time periods," Hughes explained. "This could help medical researchers and doctors predict and avoid development of drug resistance in viruses, bacteria and tumors."